title: Biocompatible functionalization of polymersome surfaces: a new approach to surface immobilization and cell targeting using polymersomes.
abstract: Vesicles assembled from amphiphilic block copolymers represent promising nanomaterials for applications that include drug delivery and surface functionalization. One essential requirement to guide such polymersomes to a desired site in vivo is conjugation of active, targeting ligands to the surface of preformed self-assemblies. Such conjugation chemistry must fulfill criteria of efficiency and selectivity, stability of the resulting bond, and biocompatibility. We have here developed a new system that achieves these criteria by simple conjugation of 4-formylbenzoate (4FB) functionalized polymersomes with 6-hydrazinonicotinate acetone hydrazone (HyNic) functionalized antibodies in aqueous buffer. The number of available amino groups on the surface of polymersomes composed of poly(dimethylsiloxane)-block-poly(2-methyloxazoline) diblock copolymers was investigated by reacting hydrophilic succinimidyl-activated fluorescent dye with polymersomes and evaluating the resulting emission intensity. To prove attachment of biomolecules to polymersomes, HyNic functionalized enhanced yellow fluorescent protein (eYFP) was attached to 4FB functionalized polymersomes, resulting in an average number of 5 eYFP molecules per polymersome. Two different polymersome-antibody conjugates were produced using either antibiotin IgG or trastuzumab. They showed specific targeting toward biotin-patterned surfaces and breast cancer cells. Overall, the polymersome-ligand platform appears promising for therapeutic and diagnostic use.
authors.affiliation: Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Egli
authors.forename: Martin G
authors.initials: MG
authors.lastname: Nussbaumer
authors.forename: Vimalkumar
authors.initials: V
authors.lastname: Balasubramanian
authors.forename: Mohamed
authors.initials: M
authors.lastname: Chami
authors.forename: Nico
authors.initials: N
authors.lastname: Bruns
authors.forename: Cornelia
authors.initials: C
authors.lastname: Palivan
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Meier
mesh_terms: D000906:Antibodies / Q000737:chemistry; D000911:Antibodies, Monoclonal / Q000737:chemistry; D061067:Antibodies, Monoclonal, Humanized; D000937:Antigen-Antibody Reactions; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D007074:Immunoglobulin G / Q000737:chemistry; D015394:Molecular Structure; D010316:Particle Size; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D013499:Surface Properties; D000068878:Trastuzumab
chemical_list: D000906:Antibodies; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D001672:Biocompatible Materials; D007074:Immunoglobulin G; D011108:Polymers; D000068878:Trastuzumab